While searching for the Jago family I came across this and may be of interest I came across this on the library of Ireland website.
Spelling variations of this family name include: Jago, Jagoe, Jagow, Jeago, Jego, Iago, Yago, Yagoe, Mac Ego and many more.
First found in Cornwall, where they were seated from ancient times.
Some of the first settlers of this family name or some of its variants were: Richard Jego, who sailed to Virginia in 1628; Walter Jago to Barbados in 1634; John, Patrick and Hester Jago to Boston in 1849; and Catherine Jago to Boston in 1850.
A more indepth look at the variants of the Jago name and places with the name.
Jago and the Irish connection:
YAGOE, or YAGOESTOWN, a parish, in the barony of SOUTH NAAS, county of KILDARE, and province of LEINSTER, 1½ mile (W.) from Ballymore-Eustace, on the road to Kilcullen; containing 612 inhabitants
This parish, anciently called St. Jago, from its church being dedicated to St. James, is situated upon the confines of the county of Wicklow. The advowson anciently belonged to the Dean and Chapter of St. Patrick’s cathedral, Dublin, and was granted in 1230 to the Earl of Pembroke, in consequence of a compact between him and Archbishop Henry, by which the Earl confirmed to him the church of Moncolumbkill, which had been granted by his father, on the condition that he and his heirs should present to a prebend of the value of fifty marks.
On the failure of issue male in the family of the Earl, it became the property of Agnes De Vesey, from whom it passed to the Earl of Kildare, whose family have ever since presented to it. It had two dependent chapels, Inchebrislane and Brethnockstown; the former, from an extensive grange belonging to the abbey of Baltinglass, obtained the name of Grangia Monachorum; that of Brethnockstown is now within the demesne of R. La Touche, Esq. The seats are Ardenode, the residence of W. Brownrigg, Esq.; Annefield, of F. Homan, Esq.; Enfield, of Capt. Dias; and Bollabeg, of Mr. Kilbee. It is a rectory and vicarage, in the diocese of Dublin, the rectory being the corps of the prebend of Yagoe, in the patronage of the Duke of Leinster; the vicarage is part of the union of Ballymore-Eustace. The tithes amount to £83.1.6., of which £27.13.10. is payable to the prebendary and £55.7.8. to the vicar. In the R.C. divisions it is also part of the union or district of Ballymore-Eustace. The ruins of the old parochial church, in a burial-ground, are within the demesne or Annefield.
Jago, Jagoe, Jagow, Jeago, Jego, TreJago and Mac Ego all seem to use the same crest below it seems the spellings later merged and some of the Jago variants died out.
A Coat of Arms was granted to a Jago family which consists of a gold shield with a black chevron between three crosses crosslet. The chevron signifies protection and has often been granted in arms as a reward to one who has achieved some notable enterprise.
The Jagow seems to share this coat of arms too but is no way part of the name as it seems to come from Germany and I see no way that it can be related to the Jago’s of Cornwall I will do some more research into this.
A search of map your name shows no other Jago variants so either they are too small or have not been counted and added into the database